Cookies are small text files in web browsers that a web server sends to a web browser in response to the browser 's request. The cookies sent by the web server, which are stored on the web client 's personal computer, are used to register user behavior: Passwords, personal data of the user, which web pages he visits most often and how long the visit duration is, etc; in other words, only data known to the browser.
Cookie files may contain the session ID. They are cached in the main memory, stored in a text file when the browser is closed, and retrieved the next time the server is called. This facilitates login procedures, but can also be used to log a visitor's usage habits and create user profiles that can be used to display banners.
Cookies, which have a maximum file size of 4 KB, are transmitted as an additional line of the HTTP line. Using the Cookie Manager, the web client can determine whether cookies are allowed or blocked and until when they are valid. In addition, the server domain can be specified and whether the cookies should only be exchanged during secure connections between the browser and the web server. Cookie filters in the Cooke manager prevent user-specific data from being transferred.
A typical cookie of a search engine contains the domain name, the expiration date, the way from where the cookie should access, the path information where the program is located, the lifetime, the name and a unique identification of the cookie. Cookies do not constitute a security risk. Thus, they constitute a facilitator when accessing websites and surfing between websites. They do not contain viruses and cannot spy on the hard disk. Cookies from companies with which there are no direct connections can be a disadvantage. Cookies from such companies should be blocked. Therefore, certain browser programs offer selective blocking options in their cookie managers.